Pass Labs INT 60 VS. Primaluna Dialogue Premium HP VS. Arcam A49

The dealer won't allow you to do an in home listening test??

Find a new dealer.

Kenepeters-

looks like you have plenty of information to digest here.

This recent Stereophile review on a speaker of equivalent retail price may have some value. The 2nd page mentions the HP able to produce satisfying performance against some upper end SS amps. Not the exact specs as your speakers, but more perspective on the HP which may be useful. 

http://www.stereophile.com/content/yg-acoustics-carmel-2-loudspeaker-0#GIFxXDoBW4Em47mP.97

All of the technical stuff mentioned along with end user worship of the HP won't replace an audition. I took a leap of faith and purchased one only because of owning a lower level model for several trouble free years. Fortunately, I  picked mine up before the MSRP increased! 

It's encouraging that Wilson Audio themselves gave a strong reply in regard to the P.L.Premium HP and didn't attempt to steer you towards SS amplifiers exclusively. This is a very good endorsement from them as they're obviously  intimately familiar with the Sasha. 
Charles 

Pass labs INT-60 is terrific.

I have always owned SS gear including a Pass XA-30.8.  The Pass was amazing.  I then sold it and purchased an HP int and sold it soon after because it did not sound "real" at all.